Brian Boru and the Battle of Clontarf

Battle of Clontarf

One of the most important events in early Irish history is the Battle of Clontarf, which occurred just over 1000 years ago in the year 1014 AD. It involves one of Ireland’s most well known High Kings - Brian Boru; Vikings, and of course, an epic battle that Irish students still learn about in school - which is saying something when you consider the many, many historical events that have come about in the last 1000 years (two World Wars, the Renaissance, the Industrial Revolution, and the invention of modern technology to name but a few!). But who was Brian Boru, what was the Battle of Clontarf, and why is it so important? Read on to find out…

Who was Brian Boru?

Brian Boru was, simply put, the last High King of Ireland, who put a stop to the domination of the O’Neills in the country and made the land free. Brian was most likely born in Killaloe, county Clare, around the year 926 or 927 AD. More than one source reports that he had reached the ripe old age of 88 during the Battle of Clontarf: other sources cite his year of birth as 923 or 942, but either way he lived to be an elderly man, especially by early medieval standards. He was born into royalty, his father being Cennetig mac Lorcain, king of what is now county Clare, and his mother Be Bionn inion Urchadh being the daughter of the king of west Connacht. The ‘Boru’ part of his name was only added after his death, and is thought to refer to either a fort near Killaloe named ‘Beal Boruma’ or its literal meaning of ‘cattle tribute’ (i.e. his all-powerful status as High King and owner of huge herds of cattle, which in those days was a measurement of wealth).

The Rise of Brian Boru

Brian was one of 12 sons, all of whom belonged to the Dal gCais tribe. Their territory was north of the Shannon Estuary (today’s county Clare), and the tribe used the river Shannon to sail downriver and raid neighbouring territories. Their biggest rival was the Viking city of Limerick, which also conducted many river-borne raids. However, they would have had at least some beneficial interactions with each other, through trading and the exchanging of skills, as by this time the Norse invaders had settled and intermingled with the previous Irish inhabitants of the land. In the year 964 one of Brian’s brothers, Mathgamain, obtained the entire kingdom of Munster when he conquered the Rock of Cashel, which had been ruled by the increasingly problem-stricken and vulnerable Eoganachta clan and which he had no legitimate rights to.

It was the beginning of a turbulent few years in the region. For obvious reasons, the Eoganachta were not best pleased with being ousted, and just about everyone else was unhappy with an illegitimate heir taking the crown. Tribes allied to the Eoganachta as well as the VIkings attempted to steal the crown from Mathgamain for themselves in a series of raids and battles. Mathgamain managed to hold onto his title until he was captured and killed by a legitimate successor, Mael Muad, in 976. However, Brian’s skills as a military leader had been underestimated by everyone, and when he took over from his brother, he quickly proved himself to be just as good a ruler, if not better. Within a year he had defeated the Viking ruler Ivan (although he allowed some of his followers to stay on in their established settlement) and within two years he had defeated Mael Muad to win back the kingdom of Munster once again in the epic battle of Belach Lechta.

Brian Boru

Taking Control of Ireland

Brian was not satisfied with that, however. He had set his sights much higher; he wanted all of Ireland under his control, and set about making it happen right away. He created a refined military strategy, using the impressive naval skills he had developed over his childhood and with the help of his Viking allies, and combining it with land attacks in a two-armed approach that overwhelmed all but the most fierce of his opponents. For some fifteen years he intermittently battled with the King of Leinster, whose base was in Meath.

Although he was never technically defeated, the King of Leinster eventually decided to relinquish control to Brian, knowing that he would still have the upper half of the country under his control from his Meath base. Brian set up his attack on the Viking city of Dublin, but the people of Leinster rallied and a strong alliance was formed in the meantime; the King’s successor Mael Morda and the Viking leader Sigtygg Silkbeard. They were still no match for Brian’s army however, who defeated them in the bloody Battle of Glen Mama.

However, while he took the land ownership for himself, Brian allowed Sigtrygg to stay on as ruler of Dublin. Next up on Brian’s hit list was the former King of Leinster, who was still ruling Ulster and Connaught from Meath, and was thus Brian’s key to all of Ireland. After much struggling, bargaining with allies, and of course, battling, the King reluctantly relinquished control once again in the year 1002.

While Connaught came to Brian’s hand relatively easily, Ulster did not. It took him a full decade of campaigning and the use of enormous military strength from all four of the other provinces to win them over, and it was still a very narrow victory only won by his unique sea-faring talents which he used to attack the Ulster coastline rather than invading by land. Brian set about consolidating his power over the entire country by allying with the only other force as powerful as him; the Church. While he was doing that however, the resentful Mael Morda rose up in rebellion in 1013 and in a battle outside the city walls of Dublin, actually managed to force Brian’s army to retreat through staying power; their opponents ran out of supplies and had no option but to head back south to Munster.

The Battle of Clontarf

Although now a seaside suburb just outside Dublin’s city centre, in 1014 Clontarf was on its outskirts, covered in fields and woodlands and facing the northern half of Dublin Bay. This was the site for one of the most important chapters in medieval Irish history, when Brian’s forces returned after their retreat with intensified vigour, and Mael Morda had to scramble to put together a military force to match to end Brian’s bloody reign once and for all. Mael Morda attempted to rally support from Brian’s allies, using his victory in the previous battle as leverage. While many of Brian’s allies refused to send troops to the opposition, they also neglected to send any to Brian too, choosing instead to remain neutral. Mael Morda then sent his long time Viking ally Sigtygg to muster troops from other Viking settlements across the water, particularly in Orkney and the Isle of Man, which was somewhat more successful - troops from both arrived five days before the battle. Brian was unperturbed by this, sending a contingent of his men to South Leinster to raid in an attempt to distract Mael Morda’s army and send them back to defend their homes. He did not bank on his reluctant ally, the former King of Leinster, withdrawing his support and his men, however, leaving him with less men than he expected and also less men than his opponents.

Brain Boru sculpture

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On 23rd April 1014 at sunrise, the battle began. On Mael Morda’s side, the overseas Vikings came out first, led by Brodir the leader from the Isle of Man and Sigurd, the leader from Orkney. Behind them came Dublin’s best fighters, followed by Mael Morda and his men. Sigtygg stayed behind the walls of Dublin with his own men, ready to defend the city against Brian if he got that far. On the other side, Brian, his family, and the rest of the Dal gCais tribe came out first, followed by the Munster men, the Connacht men, and then the former King of Leinster and his men (who had made an agreement with Mael Morda to not attack one another). The Viking men wore chain mail and used swords, while the Irish men had small spears and shields.The fighting lasted the entire day, eventually drawing to a halt at sunset.

Although there is no proven, definitive account of the events of the battle, there were certainly some very dramatic occurrences detailed in the many written accounts that followed; the Leinster king kept his own men out of harm’s way and barely participated in the battle; the fighting between the men of Connaught and the men of Dublin was so bloody that only 120 of them survived; and important bridge into Dublin was completely destroyed; Brian’s son killed 100 men alone, 50 with each arm. When the sun started to set and the tide came back in, the Viking ships that had moored in Dublin Bay were carried out to sea and a river that surrounded the battle field cut off the passage into the woods that Mael Morda’s forces had taken. They were trapped and mercilessly killed by Brian’s men, with a large number also drowning in an attempt to escape. Brian’s son, grandson and nephew were killed, leaving no heir to his throne. Sigurd and Mael Morda were also killed, leaving only the leader of the Isle of Man Vikings, Brodir, to lead the Dublin forces. Brodir hunted down Brian, and found him praying in his tent. He killed him just before he was slain by Brian’s men, at the very end of the battle.

So although they didn’t win the battle, they had ended Brian’s reign and stopped the trend of High Kings in Ireland for centuries.

Aftermath and Legacy

After the battle, things more or less went back to the way they were before Brian. The King of Leinster won back his old title, Sigtygg remained as ruler of Dublin, the Eoganacht won back their Munster kingdom, and the Dal gCais went back to their old territory to start their wars all over again, starting with attempting to overthrow the Eoganacht once again. Although Brian had two surviving sons, neither of them lived long enough to win back all their father had once had. They did however live long enough to change how future generations perceived the Battle of Clontarf: rather than viewing it as the end of an almost dictatorial reign of the most ambitious and ferocious king Ireland had ever seen, they instead turned Brian into a hero. They produced accounts telling of Brian’s victory in vanquishing the Vikings from the country, and his heroism in uniting Ireland for the first time. This is often still the account that many people hear of and learn about, when in fact the Vikings had never conquered Ireland in the first place. While they had conducted many raids on coastal and riverside towns, they soon settled down and were in fact assimilated by the Irish people. Nonetheless, Brian Boru and the Battle of Clontarf changed the course of history for several centuries, and is an important event still remembered by people today. Brian’s legacy wasn’t completely lost either; O’Brien is still one of the most common surnames in Ireland!

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